Depositional History and...Evolution of the Upper Wilcox Group and Reklaw Formation, Northern Bee County, Texas

RI0284. Depositional History and Stratigraphic Evolution of the Upper Wilcox Group and Reklaw Formation, Northern Bee County, Texas, by W. A. Ambrose, Hongliu Zeng, Jinyu Zhang, M. I. Olariu, David Smith, and Sigrid Clift. 87 p., 43 figs., 10 tables, 2018. ISBN: 978-1-970007-13-8. ISSN print: 0888-6725. To purchase a downloadable (PDF) version, please order RI0284D (doi.org/10.23867/RI0284D).

About This Publication
This publication is a detailed study of the upper Wilcox and Reklaw stratigraphic succession in a 190-mi² (~490-km²) area along the upper Wilcox shelf margin in northern Bee County, Texas. By interpreting and mapping 19 high-frequency, fourth-order regressive-transgressive sequences, the authors demonstrate that the upper Wilcox to Reklaw succession contains greater variability in depositional systems, facies, and reservoir sandstone-body geometry than was previously documented.

CONTENTS

Abstract

Introduction

Objectives

Database and Methods

Wireline-Log and Core Data

Sequence Stratigraphy

Net-Sandstone Maps

Seismic Data

Facies and Scales of Depositional Systems

Upper Wilcox Shelf Edge and Structural Controls on Deposition

Shoreline Positions

Oil and Gas Production

Geologic Framework

Upper Wilcox Stratigraphic Succession

Upper Wilcox

Upper Wilcox 2

Upper Wilcox 3

Upper Wilcox 4

Upper Wilcox 5

Upper Wilcox 6

Upper Wilcox 7

Upper Wilcox 8

Upper Wilcox 9

Upper Wilcox 10

Upper Wilcox 11

Upper Wilcox 12 and 13 (Luling Sand)

Upper Wilcox 12 (Lower Luling Sand)

Upper Wilcox 13

Upper Wilcox 14

Reklaw A

Reklaw B

Reklaw C

Reklaw D

Reklaw E

Upper Wilcox and Reklaw Shoreline Positions and Evolution of Depositional Systems

Reservoir Heterogeneity and Potential Hydrocarbon Traps

Contrasting Sandstone-Body Geometry and Reservoir Heterogeneity in Fluvial Versus Shallow-Marine Systems

Conclusions

Acknowledgments

References

Figures

1. Upper Wilcox and Reklaw chronostratigraphy in northern Bee County

2. Thickness of the upper Wilcox Group in Texas

3. Map of study area showing well control

4. Wireline-log response and core description of the Carl No. 1 Gillette well

5. Structural dip section A-A'

6. Stratigraphic dip section A-A'

7. Stratigraphic dip section B-B'

8. Stratigraphic dip section C-C'

9. Stratigraphic cross section D-D'

10. Net sandstone, wireline-log responses, initial-potential data from oil and gas wells

11. Net sandstone, wireline-log responses, initial-potential data, and selected oil and gas fields

12. Contrasting sandstone-body and facies geometry in two major types of depositional systems

13. Shoreline-trajectory chart for fourteen upper Wilcox and five Reklaw fourth-order sequences

14. Early-to-middle Eocene (53 to 47 Ma) paleogeography of the Texas Gulf Coast

15. Net sandstone, wireline-log responses, initial-potential data, selected oil and gas fields [upper Wilcox 1 sequence]

16. Net sandstone and wireline-log responses in the upper Wilcox 2 sequence

17. Instantaneous-frequency map of the Wilcox 2 sequence

18. Net sandstone, wireline-log responses, initial-potential data from gas well [upper Wilcox 3 sequence]

19. Net sandstone, wireline-log responses, initial-potential data from oil well [upper Wilcox 4 sequence]

20. Instantaneous-frequency map of the Wilcox 4 sequence

21. Net sandstone, wireline-log responses, initial-potential data from oil and gas wells [upper Wilcox 5 sequence]

22. Net sandstone, wireline-log responses, initial-potential data from oil and gas well [upper Wilcox 6 sequence]

23. Net sandstone and wireline-log responses of the upper Wilcox 7 sequence

24. Net sandstone, wireline-log responses, initial-potential data from oil and gas wells [upper Wilcox 8 sequence]

25. Net sandstone, wireline-log responses, initial-potential data from gas well [upper Wilcox 9 sequence]

26. Net sandstone, wireline-log responses, initial-potential data from gas well [upper Wilcox 10 sequence]

27. Instantaneous-frequency map of the Wilcox 10 sequence

28. Net sandstone and wireline-log responses of the upper Wilcox 11 sequence

29. Net sandstone of the combined upper Wilcox 12 and upper Wilcox 13 sequences

30. Instantaneous-frequency map of the combined upper Wilcox 12 and 13 sequences

31. Net sandstone, wireline-log responses, initial-potential data from oil and gas wells [upper Wilcox 12 sequence]

32. Core photograph from the Carl No. 1 Gillette well

33. Core photograph from the Carl No. 1 Gillette well

34. Core photograph from the Carl No. 1 Gillette well

35. Core photograph from the Carl No. 1 Gillette well

36. Core photograph from the Carl No. 1 Gillette well

37. Net sandstone, wireline-log responses, initial-potential data from oil and gas wells [upper Wilcox 14 sequence]

38. Net sandstone and wireline-log responses of the Reklaw B sequence39. Instantaneous-frequency map of the Reklaw B sequence

40. Net sandstone, wireline-log responses, and initial-potential data from oil and gas wells [Reklaw C parasequence]

41. Net sandstone and wireline-log responses of the Reklaw D sequence

42. Net sandstone and wireline-log responses of the Reklaw E sequence

43. Instantaneous-frequency map of the Reklaw D sequence

Tables

1. Recognition criteria for major depositional-system types in the upper Wilcox Group and Reklaw Formation

2. Summary of net sandstone and initial potential for facies in wave-dominated shoreline depositional systems

3. Summary of net sandstone and initial potential for facies in shelf depositional systems

4. Summary of net sandstone and initial potential for facies in fluvial-dominated delta depositional systems

5. Summary of net sandstone and initial potential for facies in fluvial depositional systems

6. Modern (Holocene) and ancient (pre-Holocene) analogs for the upper Wilcox 1, 8, and 9 sequences

7. Modern (Holocene) and ancient (pre-Holocene) analogs for the upper Wilcox 3 sequence

8. Modern (Holocene) and ancient (pre-Holocene) analogs for the upper Wilcox 1, 7, and 9 sequences

9. Modern (Holocene) and ancient (pre-Holocene) analogs for the upper Wilcox 13 sequence

10. Modern (Holocene) and ancient (pre-Holocene) analogs for the upper Wilcox 2, 4, 5, 6, and 14 sequences

Keywords: Bee County, depositional systems, oil and gas production, Reklaw Formation, sequence South Texas, stratigraphy, Texas, Wilcox Group

Citation
Ambrose, W. A., Zeng, H., Zhang, J., Olariu, M. I., Smith, D., and Clift, S., 2018, Depositional History and Stratigraphic Evolution of the Upper Wilcox Group and Reklaw Formation, Northern Bee County, Texas: The University of Texas at Austin, Bureau of Economic Geology, Report of Investigations No. 284, 87 p.